I can't possibly be the only one to have experienced this problem. my switch screws in too far, by about .080 and interrupts the power for the backup lights. the transmission is in the car or else I would just modify the lever on the valve body and i'd rather not drop the pan. the switch is beveled to seal it so I just can't space it back with a washer or gasket. any suggestions on a fix for this? does someone make a beveled spacer for this issue? I've tried different switches but the one I have is the shortest distance of the 4 I have.

They do make a beveled metal gasket that’s actually supposed to go between the switch and case. They usually come with a new switch-at least all the nos ones I have seen do.

yeah, I even tried to double up on them but didn't seal very well.

Most all the aftermarket switches have the metal center pin too long for proper operation...You'll need to file it down a little at a time until it works as it should with the switch properly torqued in place..

What’s the symptoms of a too long center pin?

Exactly what the OP is describing...The switch will work partially unscrewed but won't work completely seated..For normal operation the metal pin drops into a recess for reverse which in turn should let the pin bottom out in the plastic plunger activating the back up lights..If the center pin is too long it drops into the recess but doesn't bottom out in the plunger and can't complete the back up lamp circuit...

Pic of the switches, too long is at the top.

awesome info! thank you very much. I have 4 of these things so I will try grinding down 1 and see what happens.

thanks again for the input guys. I got it fixed. it was actually the plastic part that was making contact. had to remove about 1/8" down and use the metal beveled gasket to get it just right. removed the pan and took my time getting it there. seems like all of the aftermarket switches need to be modified to make it work. compared 4 different 727's and they all would have had this problem.

I had a problem with the aftermarket switch some years ago .Replaced it twice before realizing the problem. I buy NOS ones to have on hand when I see them on ebay.